Improvement in concrete pavements



" Frio.

GEORGE vW'. DEAN, OF STAMFORD, CONNECTICUT.

IMPRQVEMENT IN CONCRETE PAVEMENTS.

Specification formingpart of Letters Patent No. 412,444, dated September 2, 1873; application filed June 5, .1873.

To all whom it may concern:

Bc itknown that I, GEORGE W. DEAN, of Stamford, in the county of Fairfield and State of Connecticut, have invented a new and useful Improvement in Concrete Pavements, of which the following is a specification:

This invention consists in a pavement composed of coarse and ne concrete laid in a continuous and solid body, and afterward divided into blocks. The particular and essential f'eature of said invention is that the coarse concrete, of which the blocks are mainly formed, is protected on the edges and sides as well as on the upper surface by a covering of ine concrete, substantiallyT as hereinafter described.

In the accompanying drawing, which forms part of this specification, Figure I represents a plan of a walk as laid out or prepared to receive my improved pavement; Fig. 2, a longitudinal vertical section of the same; and Fig. 3, a transverse vertical section thereof. Fig. 4 is a plan, showing only the coarser blocks as Y laid, and Fig. 5 a longitudinal vertical section of the same. Fig. 6 is a longitudinal vertica-l section of the walk after the fine concrete has been laid, and Fig. 7 a plan after the concrete has been divided into blocks. Figs. 8 and 9 show a plan and longitudinal vertical section of a similarwalk in which the blocks are ornamented by fanciful inlaid designs of coloring matter.

Similar letters of reference indicate corresponding parts.

In the construction of this pavement, the material used may be Portland cement mixed with coarse gravel, clinkers, and sand, or any similar and suitable compound; but in all cases the concrete is of two grades, coarse andfiine. Thus, for the purposes of strength and economy the bulk of lthe walk is made of coarse material, requiring only a small proportion of cement; but the face and side dressing of the blocks, into which the walk is divided, is preferably either clear cement or a mixture offline sand and cement.

The manner of laying the pavement on a narrow Walk is as follows, referring, in the first instance, to Figs. 1, 2, and 3 of the drawing: I first remove the earth to the desired depth for the concrete, and roll the surface hard. Then, unless there should be a stone curbing to answer the purpose, I erect narrow boards b b along the edges of the walk, and, by setting up strips d d two inches thick, more or less, across the walk, divide .the Vsame into spaces of greater or less dimensions. I also place strips e c, about one-half the thickness ofthe parting-strips d d, against the inside of the curb-boards b b. As these parting and side strips are only used in connection with the coarse concrete, they need not be any higher than we desire to make that layer-say, two inches high en a pavement three inches thick. Having now divided the walk into boxes c c, I fill a number of the same with coarse concrete, taking them in a continuous manner, and as many of them as it may be convenient to finish off with the upper layer before the bottom layer has had time to set. After the boxes c c are thus filled with coarse concrete, and the latterwell compressed, the parting-strips d d and the side strips c e are removed, as represented in Figs. 4 and 5, leaving blocks f of coarse concretewith spaces g surroundingthem. These spaces are immediately filled with fine concrete, and the faces or top surfaces of the coarse blocks covered with the same line material, and the walk brought up to its full height. This being pressed down and beveled off with a trowel or iioat, the walk is a continuous and solidV body of concrete, as shown in Fig. 6.

The next operation is to divide the concrete into blocks, and this I do in the following mauner: Laying a straight-edge on the face of the walk in the direction and at the same places where the partingstrips were set 'up, these pointsgbeing determined by pins in the ground or marks on the curb, I take a trowel or other .suitable instrument, and, guided by the straight-edge thus applied, cut down through the center of the frne concrete, which united the blocks of coarse concrete, and thus divide the walk into as many blocks as I had formed boxes, (see Fig. 7,) each block, it being now understood, being enveloped on the sides and edges, aswell as on the face, with fine concrete.

While the strength and economy which result from'the use of coarse concrete for theV main body of the walk are indisputable, such material would not only be objectionable as regards finish, but would prevent dividing the pavement into blocks, as described, owing te the impossibility of running the knife or trowel through it; hence the necessity ot' using only fine material Where the intersections are made; but this ine concretebetween the coarse blocks not only enables ns to make these intersections, but it also serves as a protection to the blocks, keeping out dampness, and binding the two layers together, by which the scalin g ofi' of the top layer is effectually prevented; hence the use, to attain these several ends, of the parting-strips d d and the side strips e c.

The Walk being now completed, when suin ciently hard iine sand or ashes may be swept over it, and the narrow spaces between the blocks lled up; or, if it is a floor that is tiled with concrete, such spaces may be filled with putty, thereby making it Water-tight, excluding the circulation of the air, and restricting the progress of dames, il the building should be on nre.

Broad avenues that are several blocks in Width. are constructed in the same manner as the narrow walk herein described, taking the same in consecutive sections. These, too, may be laid oft' in squares, diamonds, or such forms as fancy may suggest.

If in laying Walks it is desirable to make the blocks of dii'erent colors, I lay them ofi' in the same manner as hereinbefore described, but irst ll such of the boxes only as are required of the same color, having in this case used side strips all around each box with the coarse layer, so that these isolated blocks when completed Maese may have the coverin g of line concreto on all the edges, as before described. When these blocks have become hard I till the intervening spaces with concrete, inishing oft' the surface with the color I desire, and using with the coarse layerl such strips as are necessary to attain the desired object, viz., the enveloping ofthe coarse concrete with iine. While these last-formed blocks are in a plastic state I scparate them from the others by running a knife or trowel around them, substantially as before described.

I purpose also ornamcnting the surfaces of such walks by means of patterns of various kinds, consisting of strips, letters, emblems, Src., set up in the Walk and the concrete run around them, such patterns being Withdrawn after the concrete has set, and the molds or spaces left by them filled With concrete of a different color from that of the surrounding surface. Figs. 8 and 9 illustrate such method of ornamenting the Walk.

What is here claimed, and desired to be scoured by Letters Patent, is-

A pavement for roads, Walks, and ioors, composed ot' blocks of coarse concrete,veneered on their faces and sides or edges with-tine con'- cretc, and separated one from the other, substantially as hcreinshown and described.V

' GEORGE XV. DEAN.

Witnesses:

EDWIN ScorreLD, J r., Guns. WM. KNMP, 3d. 

